The present invention relates to an improved blender with food processor capabilities for blending, mixing, processing, slicing, chopping, separating, liquefying, aerating, etc. liquids and/or solids and having preprogrammed routines for the preparation of various food items.
Blenders are household devices often used to blend or mix drinks or liquids. On the other hand, food processors are household devices commonly used to chop, cut, slice and/or mix various solid foods such as vegetables, fruits, or meats. Different blade designs and rotation speeds are used in a blender or a food processor in order to accomplish the mixing or cutting actions desired.
Conventional household blenders typically have a motor connected to a blade assembly, and the speed of the rotating blade or motor may be varied based on selections made by the user.
For example, U.S. Pat. No. 3,678,288 to Swanke et al. describes a blender having seven speed selection push buttons. The push-buttons drive slider elements which close switches so as to selectively energize various combinations of fields in a drive motor having multiple fields. Field selection provides seven speeds in a high range. Seven speeds in a low range are obtained by applying only half cycles of the AC energizing voltage to the motor when certain combinations of the switches are actuated. Once a speed selection push button is depressed, the motor is energized until an OFF switch is actuated. The device also has a jogger or pulse mode pushbutton which energizes the motor at one speed only as long as the pushbutton is depressed. Pulsing the motor on/off or at high and then low speeds permits the material being processed to fall back to the region of the cutting knives thereby improving the processing of the material.
U.S. Pat. No. 3,951,351 to Ernster et al. describes a blender having a rotary switch for selecting a high or low range of speeds and five pushbutton switches for selecting a speed within the selected range. The pushbutton switches connect various segments of the motor field winding in the energizing circuit. This device also includes a pulse mode pushbutton which causes energization of the motor only as long as the pushbutton is depressed. The motor may be energized in the pulse mode at any selected speed.
U.S. Pat. No. 3,548,280 to Cockroft describes a blender provided with 10 speed selection switches. A SCR is connected in series with the motor and has a control electrode connected to resistances which are brought into the electrode circuit by actuation of the speed selection switches to control the angle of firing of the SCR and thus the speed of the motor. This device also has a mode selection switch for selecting the manual mode or a cycling or pulse mode in which the motor is alternately energized and deenergized over a plurality of cycles, the number of cycles being set by a potentiometer controlled by a rotatable knob. In a preferred embodiment, the on and off intervals are set during manufacture but two potentiometers may be provided to enable an operator to vary the on and off times.
U.S. Pat. No. 5,347,205 to Piland describes a blender with a microcontroller for controlling energization of the blender drive motor. The speed of the motor is determined by a manual selection of N speed range selection switches, M speed selection switches, and a pulse mode switch.
Typically, the blade attachment in conventional blenders consists of two straight edge blades, a top blade and a bottom blade, joined together at a central point with their respective ends oriented in opposite directions. Because of this blender blade design, conventional blenders have limited applications because they are not able to chop, slice or cut solid food as well as food processors. Food processors, which generally operate at slower speeds than a blender, are able to better chop, slice or cut solid food because of the curved or s-shaped blade design. Liquid typically must be added to the blender in order to successfully liquefy or cut solid food into very small pieces.
Additionally, conventional blenders are not functionally preprogrammed with any motor control commands (e.g., speed, time, direction of rotation) which are automatically implemented when the user identifies a function for the blender, such as to prepare particular types of foods or drinks by selecting a button or key dedicated to the particular food or drink.
The present invention provides a blender with a novel blade unit design which has improved food processing capabilities. The blade unit comprises a first blade and a second blade of a different design from the first blade. In an exemplary embodiment of the present invention, the first blade is a straight edge blade and the second blade is a curved blade. There may also be an extraction mechanism for the blade unit.
There is also provided a blender which is programmed to accomplish predetermined functions and tasks. The programs are preprogrammed into the microcontroller of the blender and include motor commands which are automatically accessed and implemented upon selection of a desired function.
In an exemplary embodiment of the present invention, a blender comprises a base, a container, and a blade base wherein the base comprises a motor, a microcontroller, a sensor and a user interface. The microcontroller is in communication with the sensor, motor, and user interface, and can include a read only memory, a nonvolatile memory, and a central processing unit. Programs with preprogrammed motor commands are stored in the read only memory. The blade base connects the container to the base and includes a blade unit having at least a first blade and a second blade of a different design from the first blade. The user interface includes, for example, a liquid crystal display, function switches and/or light emitting diodes. Upon selection of a function, the microcontroller retrieves the respective program from the read only memory and executes the preprogrammed motor commands to accomplish the selected function.